L5 - Buffers

In previous lessons you’ve been learning about acid deposition and the effect it can have. Why doesn’t the soil in Alberta appear to be affected? Is there something about the chemical composition of soil in Alberta that prevents damage from acid deposition?

While it may appear that acid is not having a negative effect, accumulation of acids can adversely affect other systems. Consider the example of tennis. Tennis is all about short bursts of energy. Tennis can be extremely tiring because there is little time to recover between efforts. When you move to return the ball, your body metabolizes energy to allow the muscles to contract. Sometimes the exercise is so intense that your muscles accumulate lactic acid, a by-product of metabolism.

You may recall from previous science courses that the human body is designed to function within a narrow pH range. How does the human body deal with lactic and other acids that may be present? In this lesson you will investigate the properties of buffers as equilibrium systems.

Consider the following questions as you complete this lesson:

• What is a buffer and how does a buffer exhibit the characteristics of an equilibrium system?
• What is buffering capacity?